How do I block an IP address from SSH?

So I know that the Bastille script configures iptables and ipchains to protect ISPConfig and the server all together. How would I change the script to block a specific IP address? For example on my LogWatch I may have a particular IP address trying to access the root account 531 times through SSH at 4:00 in the a.m. As always I am happy with the product and response time you all have in this forum.